What is equivalent to 1 1/2

The graph shows the distance y, in inches, a pendulum moves to the right (positive displacement) and to the left (negative displacement), for a given number of seconds x. how many seconds are required for the pendulum to move from its resting position and return? enter your answer in the box.

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class

Bring the fraction a/a-4 to a denominator of 16-a^2